Laparoscopy dates back to the turn of the 20th Century. Early laparoscopic techniques were used primarily for diagnostic purposes to view the internal organs, without the necessity of conventional surgery. Since the 1930s, laparoscopy has been used for sterilization and, more recently, for suturing hernias. U.S. Pat. Nos. 4,919,152 and 4,944,443 are concerned with techniques for suturing hernias. Another recent innovation is the use of laparoscopic surgery for removing the gallbladder.
U.S. patent application Ser. No. 706,781, the application of which this application is a Continuation-in-Part, describes an apparatus and method wherein the abdominal wall is lifted away from the underlying abdominal organs by an inflatable device which is introduced laparoscopically and, once in place, inflated to engage and lift an extensive area of the abdominal wall.
Even when such lifting techniques are used, it is still necessary to retract other organs to gain access to the organ or tissue to be treated or observed. In other procedures, to gain access to the organ or tissue to be treated or observed, the organ to be treated must be separated from tissue surrounding it. To obtain the necessary retraction, current laparoscopic procedures use several small metal or plastic retractors inserted though a plurality of incisions. Because such retractors have a relatively small surface area, they tend to damage and/or cause trauma to the retracted organs or tissue. Moreover, the requirement for a plurality of incisions to heal may delay the patient's recovery.
U.S. patent application Ser. No. 794,590 (the "prior application"), of which this application is also a Continuation-in-Part, describes a number of retraction devices that are introduced into the body in a collapsed condition and, once in place, are expanded by inflating a main inflatable chamber, to retract organs or tissues and to provide access to the organ or tissue being treated. The retraction devices described in the application provide a relatively large surface area to the organ or tissue being retracted so that retraction can take place with a minimal risk of damage to the retracted organ or tissue. These relatively large retraction devices include auxiliary means for maintaining their shape after inflation, such as an additional second inflatable chamber having a cage-like structure, or a spring cage arrangement. These auxiliary means enable retraction to be maintained after the main inflatable chamber has been deflated by cutting apertures in it to gain access through the retraction device to treat the organ or tissue being treated.
The retraction devices described in the prior application provide a significant improvement in providing access to the organ or tissue being treated during laparoscopic surgery. Nevertheless, such devices have problems. When an inflatable retraction device with an auxiliary cage structure providing a retraction effect equivalent to that of the main chamber is in its collapsed state, its envelope has a significant bulk. The bulk of a retraction device in its collapsed state will be called the "collapsed bulk" of the retraction device. An inflatable retraction device that has a large collapsed bulk is difficult to package in its collapsed state so that it can be inserted into the body through a narrow trocar tube (14 mm or less in diameter). Even when the package can be made small enough, it can be a tight fit in the trocar tube, and pushing such tight-fitting packages through the trocar tube is difficult. The package tends to buckle when pushed, and consequently jams in the tube. Less bulky retraction devices are therefore desirable.
It is also desirable to have a self-retracting endoscope to simplify endoscopic observation procedures.